basis-map coefficients of A113214, shifted → basis A013609 → x ↦ x+1

only rational roots

Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernel

Recurrence

\(P_{n}(x) = \left(-4 - 2\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1-4-2-6
21616436
3-64-96-48-8-216
4256512384128161296
5-1024-2560-2560-1280-320-32-7776
6409612288153601024038407686446656
7-16384-57344-86016-71680-35840-10752-1792-128-279936
8655362621444587524587522867201146882867240962561679616
9-262144-1179648-2359296-2752512-2064384-1032192-344064-73728-9216-512-10077696
10104857652428801179648015728640137625608257536344064098304018432020480102460466176
11-4194304-23068672-57671680-86507520-86507520-60555264-30277632-10813440-2703360-450560-45056-2048-362797056
121677721610066329627682406446137344051904512041523609624222105610380902432440320720896010813449830440962176782336
13-67108864-436207616-1308622848-2399141888-2998927360-2699034624-1799356416-899678208-337379328-93716480-18743296-2555904-212992-8192-13060694016
1426843545618790481926106906624122138132481679399321616793993216125954949127197425664314887372810496245762624061444771020859637764587521638478364164096
Technical details
Node id
n-d34847103847793f · revision 0 · JSON
Definition source
derived:shift_x_plus_one
Fingerprint
f6-11aec07ce60b6d61

Observed on the stored rows ?

  • Degrees: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 (affine: slope 1, intercept 0)
  • Palindromic rows: no
  • γ-positive (gamma_positive): no
  • Nonnegative coefficients (nonn): no
  • Only rational roots (rr_by_factors: every nonzero row is a product of linear factors over ℚ): yes

Matches ?

No OEIS matches.

Submission text ?

Atlas rows n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:       1;
  1:      -4,       -2;
  2:      16,       16,        4;
  3:     -64,      -96,      -48,       -8;
  4:     256,      512,      384,      128,       16;
  5:   -1024,    -2560,    -2560,    -1280,     -320,      -32;
  6:    4096,    12288,    15360,    10240,     3840,      768,      64;
  7:  -16384,   -57344,   -86016,   -71680,   -35840,   -10752,   -1792,   -128;
  8:   65536,   262144,   458752,   458752,   286720,   114688,   28672,   4096,   256;
  9: -262144, -1179648, -2359296, -2752512, -2064384, -1032192, -344064, -73728, -9216, -512;
%F Formula
The row polynomials satisfy P(n,x) = -(4+2*x)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[-(4 + 2*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = -(4 + 2*x)*v[i - 1]); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i - 1, v[i])))};
T(9)

polytool c48629374597

Properties

Proof chains ? JSON

Same fingerprint ?

References

  1. [Bra06] Petter Brändén. On linear transformations preserving the Pólya frequency property. Transactions of the American Mathematical Society, 358(8):3697–3716, February 2006. doi:10.1090/s0002-9947-06-03856-6
  2. [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
  3. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.